Make a shortcut for the file daorigins.exe found in C:GamesDragon Agebin_shipdaorigins.exe or wherever you installed the game and got to Shortcut Properties. Under Target, add -enabledeveloperconsole at the end so it looks like this:

***: The file location will have quotation marks around it, like this "C:GamesDragon Agebin_shipdaorigins.exe". You need to make sure to add -enabledeveloperconsole AFTER the quotation marks, not inside of them, or the change will not work.

"C:GamesDragon Agebin_shipdaorigins.exe" -enabledeveloperconsole

Now, open the keybindings.ini file found in the game folder (My DocumentsBioWareDragon AgeSettings). Find the line OpenConsole_0=Keyboard::Button_X (GRAVE is default, change X to any button, [we recommend ~] that is not already used in the game.)
Then you will be able to press ~ (or the key you chose above) to open the console. Note that you will not see the console but there will be a line of symbols in the upper part of the screen as you type. You might want to press backspace a few times before you start typing just in case. Enter the following cheat codes for the desired effect:

Description: This is a comprehensive crafting guide
As such, here there be spoilers

Dragon Age has 3 schools of crafting: Herbalism, Trap Making and Poisons. Each of the 3 comes in 4 ranks: Basic (not named), Improved, Expert and Master. As long as you have the ingredients in your rather sizable inventory, you may make the items.

*** To unlock these items you need to link your Bioware account to your Dragon Age Origins account. Play Dragon Age Journeys, the Flash game, at http://www.dragonagejourneys.com.
Perform the following actions in Dragon Age Journeys to unlock the items belwo in Dragon Age Origins.

Amulet Of the War Mage

Sign in to your EA account in Dragon Age Journeys. If you do not have an existing EA

Description: You will need a code with your Collector's Edition of the game for the rare Blood Dragon Armor for this cheat. *** This also works for other Collector's Edition downloadable content -- the tome, helmet etc.

How to: Once you have entered the code and received the 1st piece of the armor and you have a merchant in your camp area with the rest of the pieces, save your game then go to the Download Content section of the main menu.
Disable the Blood Dragon Armour content (and Collector's Edition content if you have it) and reload your game. It will give you a warning but ignore it and force load the game, immediately save your game and exit to the MAIN MENU once more. Enable the things we disabled before and reload your game.
You now have 2 sets of Blood Dragon Armor! You can repeat this as needed.

How to: Follow these steps to get across the Ghost Bridge for the Urn of Sacred Ash quest:
1: Right one, right two, left three.
2: Player steps on 1st section of ghost bridge.
3: Right two, left three, left six.
4: Player steps on 2nd section of ghost bridge.
5: Right two, right four, left six.
6: Right four, left one, left six.
7: Player steps on 3rd section of ghost bridge.
8: Right four, right five, left one.
9: Right five, left one, left five.
10: Player crosses successfully.
Note that on the console version as each piece of the bridge becomes solid it remains solid permanently greatly reducing the difficulty of this puzzle.

Description: During the Tainted Blood mission in Ostargar, collect the 3 Vials of Darkspawn Blood but avoid collecting the Grey Warden Treaties. After you have the vials, chat to Duncan and choose the conversation option "We have the blood, but not the scrolls." The conversation will end and you will get experience! You can repeat the conversation and get the experience each time. You can do this all the way up to the level cap at 25 (if you are patient)! You can click through the conversation fairly quickly once you have done it a few times.
(*** This bug was repaired as part of the v1.02 patch for this game. If you want to be able to take advantage of it, do not install the patch.)

Description: This is a comprehensive crafting guide (Pt 2)
As such, here there be spoilers

Dragon Age has 3 schools of crafting: Herbalism, Trap Making and Poisons. Each of the 3 comes in 4 ranks: Basic (not named), Improved, Expert and Master. As long as you have the ingredients in your rather sizable inventory, you may make the items.

Description: In the origins stories, be sure to remove all the items of those that accompany you (and leave your party) prior to their departure. You may need to save the gaem more often. You can use these items to sell or equip as needed.
Another example: once you return from the Kokori Wilds, before talking to Duncan, remove all the equipment from Jory and Daveth since they are destined to die.

Description: This has only been tested on the original release. A "sacrificial" stat is required -- one you do not need (for a Mage that would be Strength; for a Warrior or Rogue, Magic works). Head to the level up screen and put all of your points into the sacrificial stat. Click Next, then click Previous and then hit Reset. Manually remove the points to the sacrificial stat. You should now have 6 points rather then the 3 you put in. Choose Next a few times and then choose Play to save the changes made. Repeat this process. When the stat turns negative the game will regard it as 0 but you will still be getting points for it. However, in order to bring the stat back up you must put the amount you took from it back in, which is why the stat is "sacrificial." The most you can put in at a time is 100 points.

How to get the three class levels trophies/achievements (WITCH HUNT DLC ONLY!!!)

100%

Ok so what you need to do is create 1 rogue character in DAO,1 warrior character,1 mage character, then you need to get to lothering with all three of them, save with each of them, then, import them 1 by 1 to witch hunt and you will level up to level 20 then you will get the 3 class level 20 achievements/trphies